I can't resist Don DeGraaf's invitation to try to define intelligent design.
So I'll take a crack at a substantive definition, or perhaps, a discussion
of the concept leading up to a definition, and others can let me know if it
makes any sense.

1. Intelligent design is an extension of the concept of a biological
_system_. "A 'system' is defined as a complex of elements in interaction,
these interactions being of an ordered (non-random) nature," according to
Ludwig von Bertalanffy, generally considered the father of general systems
theory. The emphasis is more on the interactions than on the elements
themselves. Non-randomness is a critical criterion of systems and thus of
design. I will call this a "Bertalanffian system".

2. Mike Behe adds the concept of a function or purpose to the definition.
"Design is evident when a number of separate, interacting components are
ordered in such a way as to accomplish a function beyond the individual
components." It is impossible to define design either as a noun or a verb
without implying purpose or intent. Design is teleological, or teleonomic as
Franklin Harold called it. Mike places more emphasis on the components more
than Bertalanffy does who emphasizes the interactions. Bertalanffy has the
better concept, I think, because design resides relatively more in the
relationship of the components than in the components. The concept of design
then may be expanded to read "a Bertalanffian system with purpose(s)."

3. Perhaps purpose may be eventually be described as a vector, having both
direction and magnitude. This suggests that a design is a "vectored system."

4. The question of the relation of form to function needs to be discussed.
Form means morphology and anatomy. Function means some action or behavior.
What comes first, form or function? Does new form lead to new function, or
does new function lead to new form? To illustrate (crudely): Did a change
or maturation of the hominid nervous system (form) make upright
bipedal-walking (function) possible and thus the abilityy to survey the
savannah; or did the need survey the savannah (function) result in the change
in the nervous system (form), making bipedal-walking possible? Design theory
would hold that change in form comes first, resulting in new possibilities of
action later. Darwinism, I believe, consistently holds that function (the
need for action) comes first and shapes and changes form so as to attain the
action. Determining whether form preceded function in any given case, or the
other way around, is extraordinarily difficult, and probably is conditioned
more by one's presuppositions than by open-minded reading of data. Design
then means _predesign_ in the sense that design precedes function. So the
definition may be expanded to "a predesigned Bertalanffian system
potentiating new behavior(s) or function(s)." This is all getting pretty
abstract, I fear.

5. Adding the word "intelligent" to design introduces the concept of _agent_
in design theory. The agent will probably be universally interpreted as God.
The addition extends design theory beyond the domain of methodological
naturalism by planting one foot of the theory in natural theology.
"Intelligent design" bridges the natural and non-natural domains. The
argument for intelligent design is, in part, an analogical one. Using many
examples of design where an agent is obvious, such as Paley's watch,
intelligent designers in biology also imply the action of an intelligent
agent beyond the natural order.

6. In summary, intelligent design is "a predesigned complex of elements in
interaction, these interactions being of an ordered (non-random) nature, that
potentiates new behavior(s) or function(s), all brought about by an agency
beyond
the natural order."

I'm not sure how this definition can be operationalized so that instances of
it can be observed and agreed upon by competent scientists. Behe says the
critical criterion is irreducible complexity. Bertalanffy makes it
non-random ordering of relationships among the elements in the complex
system. I would add the criterion that form precedes function. Dembski said
(Mere Creation conf.) that if you can rule out the operation of law and
chance as critical causal factors in a given phenomenon, the third and
remaining option is design. Whether these criteria can be refined enough to
serve as observational criteria remains to be seen. Much work remains to be
done.

These are my thoughts on intelligent design. Any comments or improvements
anyone?